Forward scanning-optical probes, circular scan patterns, offset fibers

Abstract

An optical light scanning probe is presented, the probe comprising a handle, shaped for grasping by a user; a cannula, protruding from a distal portion of the handle with an outer diameter smaller than 20 gauge; an optical fiber with a distal fiber-portion off a probe-axis, configured to receive a light from a light-source at a proximal fiber-portion, and to emit the received light at the distal fiber-portion; a fixed beam forming unit, disposed at a distal portion of the cannula, configured to receive the light from the distal fiber-portion, and to deflect the received light toward a target region; and a fiber actuator, housed at least partially in the handle, configured to move the distal fiber-portion to scan the deflected light along a scanning curve in the target region.

The invention claimed is: 
     
       1. An optical light scanning probe, comprising:
 a handle, shaped for grasping by a user; 
 a cannula, protruding from a distal portion of the handle with an outer diameter smaller than 20 gauge, wherein an outermost surface of the cannula comprises an outermost surface of a portion of the scanning probe; 
 a rotation tube rotatably positioned within the cannula, wherein a distal end of the rotation tube comprises an eccentric hole positioned off a probe-axis, the eccentric hole having a central axis parallel to the to the probe-axis; 
 an optical fiber comprising a distal fiber-portion positioned within the eccentric hole such that the distal fiber-portion is off the probe-axis and parallel to the probe-axis, the optical fiber configured
 to receive a light from a light-source at a proximal fiber-portion, and 
 to emit the received light at the distal fiber-portion; 
 
 a beam forming unit fixedly attached to the cannula and disposed at a distal portion of the cannula, the beam forming unit comprising at least one of a GRIN lens, a lens, a lens system, or a focusing element configured
 to receive the light from the distal fiber-portion, and 
 to deflect the received light toward a target region; and 
 
 a fiber actuator, housed at least partially in the handle, configured to rotate the rotation tube within the cannula such that the distal fiber-portion positioned within the eccentric hole rotates around the probe-axis relative to the beam forming unit to scan the deflected light along a scanning curve in the target region, wherein 
 the probe-axis is one of a cannula-axis and a beam forming unit-axis. 
 
     
     
       2. The optical light scanning probe of  claim 1 , the scanning curve comprising one of:
 an open curve, an arc, a closed loop, a circle, a cycloid, and an ellipse. 
 
     
     
       3. The optical light scanning probe of  claim 1 , wherein:
 the fiber actuator is configured to be controlled by an actuator controller, positioned at least partially outside the probe. 
 
     
     
       4. The optical light scanning probe of  claim 1 , the fiber actuator comprising: a motor, configured to rotate a hollow torque cable that has a distal portion inside the cannula, wherein the hollow torque cable is configured
 to rotate the rotation tube when rotated by the motor, 
 to house a portion of the optical fiber that extends into the cannula to guide the optical fiber to the eccentric hole. 
 
     
     
       5. The optical light scanning probe of  claim 4 , wherein: the hollow torque cable houses the optical fiber rotatably so that the motor of the fiber actuator can rotate the torque cable without twisting the optical fiber. 
     
     
       6. The optical light scanning probe of  claim 5 , wherein:
 the hollow torque cable houses the optical fiber in a non-rotatable manner. 
 
     
     
       7. The optical light scanning probe of  claim 6 , wherein:
 the optical fiber is coupled to a light guide through an optical rotary connector. 
 
     
     
       8. The optical light scanning probe of  claim 5 , wherein:
 the distal fiber-portion is disposed one of
 distal to a distal end of the hollow torque cable, and 
 proximal to the distal end of the hollow torque cable. 
 
 
     
     
       9. The optical light scanning probe of  claim 5 , wherein:
 a distal end of the hollow torque cable is disposed one of 
 distal to a distal end of the rotation tube, and 
 proximal to the distal end of the rotation tube. 
 
     
     
       10. The optical light scanning probe of  claim 5 , wherein:
 the motor is housed outside the handle. 
 
     
     
       11. The optical light scanning probe of  claim 1 , wherein:
 the beam forming unit comprises the GRIN lens coupled to at least one of a glass element, a no-core fiber, and a glass rod. 
 
     
     
       12. The optical light scanning probe of  claim 1 , wherein:
 the beam forming unit comprises a relay lens. 
 
     
     
       13. The optical light scanning probe of  claim 1 , wherein:
 a portion of the fiber actuator is positioned in a non-disposable portion of the handle. 
 
     
     
       14. The optical light scanning probe of  claim 1 , wherein:
 a portion of the fiber actuator is positioned in a disposable portion of the handle. 
 
     
     
       15. The optical light scanning probe of  claim 1 , wherein:
 a portion of the fiber actuator is positioned in a console, comprising an Optical Coherence Tomography imaging engine. 
 
     
     
       16. The optical light scanning probe of  claim 1 , wherein:
 the scanning probe is part of at least one of a laser coagulation system and a laser ablation system. 
 
     
     
       17. An optical imaging system, comprising:
 an Optical Coherence Tomography engine, comprising
 an imaging light source, and 
 an OCT image detector-processor; and 
 
 an imaging probe, comprising
 a handle, and 
 a cannula, protruding from a distal portion of the handle with an outer diameter smaller than 20 gauge, wherein an outermost surface of the cannula comprises an outermost surface of a portion of the scanning probe; 
 a rotation tube rotatably positioned within the cannula, wherein a distal end of the rotation tube comprises an eccentric hole positioned off a probe-axis, the eccentric hole having a central axis parallel to the probe-axis; 
 
 an optical fiber comprising a distal fiber-portion positioned within the eccentric hole such that the distal fiber-portion is off the probe-axis and parallel to the probe axis, the distal fiber-portion configured to guide a light from the imaging light-source; 
 a beam forming unit fixedly attached to the cannula and disposed at a distal portion of the cannula, the beam forming unit comprises at least one of a GRIN lens, a lens, a lens system and a focusing element to form a beam by focusing the received light, or a focusing element configured to deflect the guided light toward a target; and 
 a fiber actuator, housed at least partially in the handle, configured to rotate the rotation tube within the cannula such that the distal fiber-portion positioned within the eccentric hole rotates around the probe-axis relative to the beam forming unit to scan the deflected light along a scanning curve in a target region, wherein 
 the probe-axis is one of a cannula-axis and a beam forming unit-axis. 
 
     
     
       18. A method of imaging with an imaging probe that comprises a handle; a cannula, protruding from the handle with an outer diameter smaller than 20 gauge, wherein an outermost surface of the cannula comprises an outermost surface of a portion of the scanning probe; a rotation tube rotatably positioned within the cannula, wherein a distal end of the rotation tube comprises an eccentric hole positioned off a probe-axis and perpendicular to the probe-axis; an optical fiber comprising a distal fiber-portion positioned within the eccentric hole such that the distal fiber-portion is off the probe-axis, the eccentric hole having a central axis parallel to the probe-axis; and a beam forming unit fixedly attached to the cannula at a distal portion of the cannula; the method comprising:
 receiving a light by the optical fiber from an imaging light-source at a proximal fiber-portion; 
 emitting the received light by the optical fiber at the distal fiber-portion towards the beam forming unit fixedly attached to the cannula; 
 deflecting the emitted light by the beam forming unit; and 
 rotating the rotation tube within the cannula such that the distal fiber-portion positioned within the eccentric hole rotates around the probe axis relative to the beam forming unit by a fiber-actuator, housed at least partially in the handle of the imaging probe to scan the deflected light along a scanning curve in a target region, wherein 
 the probe-axis is one of a cannula-axis and a beam forming unit-axis.